Dehydroepiandrosterone, also known as prasterone, 3-hydroxyandrost-5-en-17-one, dehydroisoandrosterone, trans-dehydroandrosterone, or .DELTA..sup.5 -androsten-3-.beta.ol-17-one (referred to hereinafter as "DHEA"), is a 17-ketosteroid, which is quantitatively one of the major adrenocortical steroid hormones present in the metabolism of humans and other mammals. S. Budavari, ed., Merck Index, Eleventh Edition (1989). This endogenous androgenic steroid has been shown to have a myriad of biological activities. An assortment of prior art has recognized the plethora of beneficial effects of DHEA, its sulfate ester (DHEA-S) and salts thereof. DHEA is readily interconvertible in vivo with DHEA-S through the action of intracellular sulfatases.
In U.S. Pat. No. 4,920,115 to Nestler et al., oral dosages of DHEA given to healthy male individuals were shown to reduce body fat mass, increase muscle mass, lower LDL cholesterol levels without affecting HDL cholesterol levels, and not affect tissue sensitivity to insulin in human patients. Nestler et al. described the use of pharmaceutical preparations of DHEA as a preventative means to avoid development of atherosclerosis.
U.S. Pat. Nos. 5,110,810 and 5,162,198 issued to Eich et al., disclose methods for treating human beings with pharmacological quantities of DHEA, resulting in increased serum DHEA and DHEA-S in their blood, which lowers rates of platelet aggregation. By reducing the rate of platelet aggregation, the incidence of morbidity and mortality from vascular events such as myocardial infarction and stroke, as well as the occurrence of restenosis following vascular interventions, can be significantly reduced.
U.S. Pat. No. 4,835,147 to Roberts demonstrated that administration of DHEA or its therapeutically acceptable salts to individuals ameliorated symptoms of prostatic hypertrophy, certain symptoms of menopause, particularly those related to nervous system dysfunction, and of psycho-sexual dysfunction, symptoms such as inhibited sexual desire, inhibited sexual excitement and inhibited orgasm.
Other widely varying medical uses for DHEA have been reported. U.S. Pat. No. 4,628,052, issued to Peat, reports using either an oral or topical preparation of DHEA to treat rheumatoid arthritis, osteo-arthritis and arthritis associated with psoriasis and with lupus and other auto-immune diseases, and also for treating non-specific joint pain associated with stress or incidental to other ailments.
DHEA compounds have also been established to have a beneficial effect as an anti-diabetic agent. See U.S. Pat. No. 4,518,595 to Coleman et al.
In the medical literature, many favorable reports of medical benefits to individuals due to increased levels of DHEA and its sulfate ester, DHEA-S, have been reported as well. Geriatrics 37:157 (1982) stated that DHEA was a "miracle" drug, which may prevent obesity, aging, diabetes mellitus and heart disease. Barrett-Conner et al. produced studies which revealed an inverse relationship between cardiovascular death and serum DHEA-S levels in adult men. N. Engl. J. Med. 315:1519 (1986). Arad et al. in Arteriosclerosis 9:159 (1989) and Gordon et al. in J. Clin. Invest 82:712 (1988) both describe the reduction of atherosclerosis plaque formation by DHEA.
One of the most important uses of DHEA has been to improve the immune response in human beings. U.S. Pat. No. 5,077,284, issued to Loria et al., describes the administration of DHEA, either orally or by subcutaneous injection, to provide very high levels of protection against viral, bacterial, fungal or parasitic infections in immuno-compromised animals and humans. The experimental animal data, described by Loria et al., demonstrated that in infection (100,000 plaque forming units/animal) of a human coxsackievirus B4 strain, which causes mortality in about 90% of infected animals, mortality was reduced to 37% when animals were treated with DHEA. Moreover, Loria et al. demonstrated that administration of DHEA induced an 80% elevation in the number of antibody forming cells within the animal. In virus infected and DHEA treated animals, there was also an elevation in the number of monocyte cells, the particular white blood cells associated with a resistance to coxsackievirus infection. This elevation was not observed in uninfected animals that were treated with DHEA. This observation demonstrates that DHEA can be used to up-regulate the host immune response to virus infection, by increasing the number of antibody forming cells, elevating the number of white blood cells associated with resistance to virus infection and markedly reducing virus induced mortality.
Although DHEA is the most abundantly produced adrenal steroid and serum concentrations of its sulfate ester, DHEA sulfate (DHEA-S), are approximately 20 fold higher than those of any other circulating steroid hormone, levels of this hormone begin to decline within individuals during the second decade of life, reaching 5% of the original level in the elderly.
Peak serum DHEA and DHEA-S levels occur when a patient is approximately 25 years old and decline over the ensuing decades. Ohrentreich et al. found that mean DHEA-S levels and ranges for adult men were as follows: Ages 25-29 (3320 ng/ml); ages 45-49 (1910 ng/ml); ages 65-69 (830 ng/ml). See J. Clin. Endocrinol. Metab., 59:551 (1984). Similar age related decline in serum DHEA-S levels were found to occur in women. Correspondingly, the incidence of cardiovascular disease in human beings increases with age, thus suggesting an epidemiological relationship between serum DHEA and DHEA-S levels in cardiovascular disease. In Barrett-Conner et al., supra, the base line DHEA-S levels of 242 middle aged men (ages ranging between 50 and 79 years) was compared to the subsequent 12 year mortality rate of the men from any cause, from cardiovascular disease, and from ischemic heart disease. DHEA-S levels were significantly lower in men with a history of heart disease compared to those without. In men with no history of heart disease, the age-adjusted relative risk associated with DHEA-S levels below 140 .mu.g/dl was 1.5 (p NS) for death from any cause, 3.3 (p&lt;0.05) for deaths from cardiovascular disease, and 3.2 (p&lt;0.05) for deaths from ischemic heart disease. An increase in DHEA-S level of 100 .mu.g/L had a 48% reduction in mortality (adjusted for other risk factors) from cardiovascular disease (p&lt;0.05).
Further Eich et al. supra, demonstrated that treating human beings with pharmacological quantities of DHEA resulted in increased serum levels of DHEA and DHEA-S. Eich et al. performed in vivo experiments using a test group of 10 male human being subjects. In these experiments, DHEA was administered in a double-blind placebo controlled trial in an amount of 300 mg of DHEA per day in the form of 100 mg capsules taken orally 3 times a day. The study found that the initial baseline serum DHEA prior to conducting the experiment was 5.83+/-3.9 ng/ml, and the mean serum DHEA during the second week of investigation for the placebo group was 5.58+/-4.1 ng/ml. The mean serum DHEA for the treated group during the second week investigation was 28.7+/-13.9 ng/ml. In addition, the baseline serum DHEA-S was 316.2 .mu.g/dl and during the second week, the mean serum DHEA-S level was 260.5+/-56.7 .mu.g/dl in the placebo group, and 1451.9+/-56.7 .mu.g/dl in the DHEA group. Elevation of serum DHEA-S levels when a patient is receiving only supplemental DHEA suggested that DHEA-S serves as a storage pool for DHEA, which is the active form of the hormone. The rate of platelet aggregation for the human subjects participating in this study was examined prior to treatment with supplemental DHEA and was again tested on three different occasions during the second week of an investigation. Four of the five test subjects who received the DHEA supplement demonstrated a slower rate of aggregation and a requirement for higher concentration of arachidonic acid to initiate aggregation. Thus, the elevated serum DHEA level slowed platelet aggregation which can significantly reduce the incidence of morbidity and mortality from vascular events such as myocardial infarction and stroke.